fc.studio those files are not "visible" they should be extracted from the AmigaOS ROM Update that is located in devs:
How? Simple from the AmiKit package use a tool that is named extractmodule or something like that. Docs for it are in the package.
On the other hand, going this route means, you will afterwards need another tool called loadmodule, in order to manually load that patched files on startup.
Anyway, if you carefully read the docs in the Amikit package you should solve all your troubles.